Undulating-current apparatus.



F. GEDERGREN.

UNDULATING CURRENT APPARATUS.

APPLIOATION FILED OOT.7, 1907.

Patented Feb. 23, 1909.

2 SHEETS-SHEET 1.

P. CEDERGEEN,

UNDULATING CURRENT APPARATUS.

APPLIUATION FILED 0OT.7, 1907.

Patented Feb. 23, 1909.

2 SHEETS-SHEET 2.

FRED CEDE-RGBEN, ()F-H-AJ/MOND,

INDIANA,,5A SSIGNOR OF ONE-HALF T FRANK S. BETZ, OF HAMMOND, INDIANA.

minimums-emanate: arnesa'rus.

' Specification of Letters Patent.

Patented Feb. as, 1909.

Application filed. Getober 7, ram; serial to. 396,252.

To all whom it may concern:

Be it known that I, FRED CEDERGREN, a citizen of the United States of America, and a resident of Hammond, Lake county, Indiana, have invented certain new and useful Improvements in Undulating-Uurrent Apparatus, of which the following is a specification.

The main objects of this invention are to provide an improved form of apparatus for producing from one source intermittent, alternating and undulatory electric currents having different characteristics; to provide a device of this character in which by simple adjustment the ra idity of the pulsations of the current may e readily adjusted; to ro-' vide an improved device in which the ma ring and breaking of an electric current, due to the movement of a vibrating armature of a magnet, may be utilized for producing an alternating or undulating current in another electric circuit; to provide an improved construction for electro-magnets having oscillating armatures, and to provide in such devices improved means for limiting the amplitude of the oscillations of the armature, and an im roved form of stop for controlling such o'sc' ations. These obyects are accomplished b the device shown in the accompanying rawings, inwhich-- Figure 1 is a diagrammatic representation of an apparatus constructed according to this invention for producing intermittent alternating and undulating electric currents. Fig. 2is a top plan of the same, omitting the electrical connections. Fig. 3 is a side elevation of the device shown in Fig. 2. Fig. 4

r is a detail, partly in section, of the mechanism for adjusting'the sto' for the vibrating armature. Fig. 5 is a etail showing the locking screw which clamps the adjustment shown in Fig. 4 so as to prevent shifting of the stop. Fig. 6 is a detail of the plate upon which the locking screw shown in Fig. 5 bears. Fig. 7 is a top plan, partly broken away, of the armature and the contact disk or'commutator.

p The device shown in the drawings comprises a base 1, havin mounted thereon an electro-inagnet, the .po es of which are designated 2 in Fig. 2, thecoils 'being' designated 3.

' 4 of Fig. 3 re resents the] oke connecting the cores of t e coils 3. e supporting frame comprises a air of uprights 5 mounted on the base 1, and connected at their upper ends by a cross-piece 8.

. A spindle 9, pivotally mounted between the base 1 and the cross-bar 8 midway between the cores of the magnet, carries at its upper end thearmature 10. The armature 10 is rigid on the spindle 9, and said spindle is connected with the inner end of a spiral spring 11, whose outer end is connected with an arm 12 carried by an adjustable collar 13 on the lower bearing 14 of the spindle 9. The spring 11 normally urges the armature 10 in the direction of the arrow 15 of Fig. 2, and when the magnet is energized it draws the armature in the opposite direction against the action of said s ring. A-fiat spring secured to one side oft e armature 10 provides the spring stop armslt and 17, which yieldingly stop and reverse the movement of the armature in each direction. The arm 16 is provided with a platinum contact adapted to make electrical connection with an adjustable contact screw 18 mounted on the upright 19.

The conductors of the actuating circuit are designated A in Fig. 1, and include the windings 3 of the magnet, the spring arm 16 of the armature, and a source of current which is indicated as a battery 20. The conductors of the circuit whose current is to be varied are indicated at B in the drawings, and include,'in the device shown, the atients binding posts P, the battery 21, t e brushes 22 and 23, and the contacts 24, 25 and 26 of the commutator 27. The commutator 27 has a series of contact points, upon which the brushes bear, and alternate contact points are connected with opposite leads of the battery circuit B, so that an oscillating movement of the commutator will cause successive reversals of the current in the patients cFircuit B, as will be readily understood from The swingin' of the armature 10 in the direction opposi e that of the arrow 15 is limited through contact of the spring arm 17 with the stop arm 29. The stop arm 29 has a journal 30 rotatably mounted in the crossbar 8, as shown in Fig. 4, and provided with upwardly disposed threaded extension 31 upon which is mounted a nut 32 and a handle 33. The handle 33 is rigidly secured to the end of spindle 9.-

V of the current.

extension 31, and serves for adjusting the position of the arm 29 about the axis of its journal. The upper bearin of the spindle 9 comprises a screw 34, whidh extends longitudinally through the journal 30 andlias a conical point seated in a socket in the upper A disk or washer 36 is mounted on the bar 8 concentrically of .the journal 30, and serves as a surface against which the locking screw 35 bears for locking the handle 33 in any desired position. The locking screw 35 is provided with a knurled head,=so that it may be readily rotated.

The operation of the device shown is as follows: When the circuit A is closed, the magnet will be energized, and the armature thereof will be swung in a counter-clockwise direction. This movement of the armature breaks the circuit at the contact 18 and deenergizes the magnet, but the momentum of the armature causes it to swing until stopped by the engagement of the spring arm 17 with the stop arm 29. The spring 11 then returns the armature to its initial position, again completing the circuit A, and thereby causing the energizing of the magnet and so on, the armature oscillating between the stop arm 29 and the contact 18. The oscillation of the armature 10 causes intermittent changes in the direction of the current in the circuit B, or alternate making and breaking of said circuit, or any desired combination of changes in direction and breaks in the current, depending upon the arrangement and spacing of the contacts of the commutator,

andalso depending uponthe amplitude of the oscillations of the armature 10. The stop 29 may be adjusted so that the vibration of the armature will be fast and of short am litude, or of lon amplitude and slow. This adjustment of the stop 29 is made by loosening the lock screw 35-, and turning the handle 33 to bring the stop 29 to the desired angular position. The stop arm 29 may be adjusted so that the amplitude of the vibration of the armature 10 is just sufficient to shift the brushes one contact space, thereby producing an alternating current in' the patients circuit B, or it may be adjusted so that the am litude of oscillation is so great that there will be intervals in which the circuit is broken between successive reversals The position of the stop 29, therefore, determines the frequency of the alternation and the character of the undulations in the patients circuit.

What I claim as my invention, and desire to secure by Letters Patent, is:

1. An apparatus of the class described, comprising an electro-magnet, an armature mounted to oscillate at the poles of said magnet, a commutator mounted to oscillate through the oscillation, of said armature and having thereon a plurality of contacts, brushes bearing on said contacts and connected in an electric circuit, said contacts being insulated from each other and connected in said circuit so as to cause changes in the direction of the current in the circuit through the oscillation of said comn'iutator, and means for changing the amplitude of the oscillation of said commutator.

2. The combination of an electro-magnet, an actuating circuit therefor, a balanced armature pivotally mounted between the oles of-said magnet and free to swing wit out contact therewith, a contact on said armature connected with one conductor of said circuit, asecond contact connected with another conductor in said circuit and adapted to engage with the first contact to close said circuit when the armature is in a certain position away from the poles of the magnet, means normally urging said armature toward said certain position, said circuit being broken when said armature is attracted by the magnet, and an adjustable stop forlimiting the movement of said armature away from said second contact, all being arranged to cause said armature to oscillate through a predetermined angular interval and to ermit said interval to be varied at the w' l of an operator.

3. The combination of an electro-magnet, an actuating circuit therefor, a balanced armature pivot'ally mounted between the 3010s of said magnet and free to swing wit out contact therewith, a contact on said armature connected with one conductor of said circuit, a second contact connected with another conductor in said circuit and adapted to engage with the first contact to close said circuit when the armature is in a certain position away from the poles of the magnet, means normally urging said armature toward said certain position, said circuit being broken when said armature is attracted by the magnet, an adjustable stop for limiting the movement of said armature away from said second contact, said stop comprising an arm pivotally mounted in axial alinemcnt with said armature and having a part extending into the path of said armature, and means for clamping said arm in different angular ositions.

4. he combination of an electro-magnet, an actuating circuit therefor, a balanced armature pivotally mounted between the oles of said magnet and free to swing wit iout contact therewith, a contact on said armature connected with one conductor of said circuit, a second contact connected. with another conductor in said circuit and adapted to engage with the first contact to close said circuit when the armature is in a certain position away from the poles of the magnet, means normally urging said armature toward said certain position, said circuit being broken when said armature is attracted by the magnet, an adjustable stop for limiting the movement of said armature away from said second contact, said stop comprising an arm pivotally mounted in axial alinement with said armature and having a part ex tending into the path of said armature, means for clamping said arm in difierent angular positions, and a spring inter osed between said armature and stop an adapted to cushion the contact between them.-

5. The combination of an electro-magnet, an actuating circuit therefor, a balanced armature pivotally mounted between the oles of said magnet and free to swing witiiout contact therewith, a contact on said armature connected with one conductor of said circuit, a second contact connected with another conductor in said circuit and adapted to engage with the first contact to close said circuit when the armature is in acertain position away from the poles of the magnet, means normally urging said armature toward said certain position, said circuit being broken when said armature is attracted by the magnet, an adjustable stop for limiting the movement of said armature away from said second contact, said stop comprising an arm pivotaliy mounted in axial alinement with said armature and having a part extending into the path of said armature, a fixed support for said stop arm, and a looking screw bearing between said arm and said su port for locking said arm in different an an actuating circuittherefor, a balance ar mature pivotally mounted between the dies of said magnet and free to swing wit out contact therewith, a contact on said armature connected with one conductor of said circuit, a second contact connected with another .conductor in said circuit and adapted to engage ,with the first contactto close said circuit when the armature is in a certain position away from the poles of the magnet, means normally urging said armature toward said certain position, said circuit being broken when said armature is attracted by the magnet, an adjustable stop for limiting the movement of said armature away from said second contact, a commutator secured in axial alinernent with said armature and rotatable therewith, brushes bearing on said commutator, and an electric circuit including said brushes and commutator and separate from said actuatin circuit.

Signed at Chicago this 31st day of August 1907.

FRED CEDERGREN. 

